According to a typical known technique, a display such as a liquid crystal display is installed in a cab of a work machine such as a wheel loader and a motor grader, and plural kinds of state information of the work machine, which include driving speed, engine speed, hydraulic oil temperature, torque converter oil temperature and fuel amount, are displayed on a screen of the display (see, for instance, Patent Literature 1). An operator of the work machine operates the work machine, monitoring the screen.
According to another known technique, a display in a wheel-type work machine is capable of switching information on a screen. Specifically, during the traveling of the work machine, the screen shows information including driving speed and engine speed, whereas, when the work machine is in operation (e.g., a crane of the work machine is in operation), the screen shows information including the lifting state of the crane (see, for instance, Patent Literature 2).
Further, according to still another known technique, a screen, which normally shows the state information of a work machine, shows a caution sign in the case of a malfunction of a part of the work machine (see, for instance, Patent Literatures 3 and 4).